The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 24, 2002
Filed:
Feb. 20, 2001
Kazuki Yokota, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
An alignment mark set is provided, which facilitates the formation of a desired contour of each alignment mark and which suppresses the degradation of measurement accuracy for alignment of patterns. This alignment mark set comprises: (a) a first alignment mark formed in an exposure area; the area having a periphery, first central axis, and a second central axis perpendicular to the first axis; the first alignment mark being located near the first central axis and apart from the second axis; (b) a second alignment mark formed in the exposure area; the second alignment mark being located near the second central axis and apart from the first axis; and (c) when the exposure areas are regularly arranged in such a way as to have a same orientation in a plane, each of the first and second alignment marks in one of the sets is not located close to the first and second alignment marks in another of the sets, thereby ensuring irradiation of exposing light to all the areas. It is preferred that each of the first and second marks is square.